Hi Ravi -
Interesting question - Tableau doesn't do any sort of "change tracking" against the data it reports on. I'm not sure if you're asking for that functionality, or if you already have a mechanism that does that and you want to highlight records where "current value" <> "old value": for a particular row.
Please expand on your question a little bit?
what i mean is i want to show user about recently added records on dasboard using color legend.is it possible through any caluculation ?